The components known in of the art based upon amorphous silicon or its alloys are comprised of two antiserially-arranged pin or nip diodes for forming a pinip structure or a nipin structure. The diodes are here arranged substantially perpendicular to the incident light direction.
Such an nipin structure having a photosensitive electronic component based upon amorphous silicon is known for example from U.S. Pat. No. 5,311,047. It is known to optimize such a nipin structure with reference to the spectral sensitivity dependent on the voltage applied to this structure.
The incorporation of additional intrinsically conducting layers on both sides of the p-doped layer with a band gap between 1.74 eV and 1.9 eV, can improve the blue/green sensitivity in of an nip structure in the incident light direction or the red/green separation in a following pin structure in the incident light direction. (Q. Zhu, H. Stiebig, P. Rieve, J. Giehl, M. Sommer, M. Bohm, "NEW TYPE OF THIN FILM IMAGE SENSOR" in Sensors and Control for Advanced Automation, edited by M. Becker, R. W. Daniel, O. Loffeld, Proc. SPEI 2247 (1994) 301).
It is known to absorb blue light preferentially in the first intrinsically-conducting (i) layer, to absorb green light in the front part of the intrinsically-conducting layer and rear diode and to absorb red light by reduction of the .mu..tau. product in the rear part of the second intrinsically-conducting layer. For that purpose a nipin structure is used in which one or more additional intrinsic layers are provided. (H. Stiebig, J. Giehl, D. Knipp, P. Rieve, M. Bohm, AMORPHOUS SILICON THREE COLOR DETECTOR in MRS Symp. Proc. 377 (1995) 813 or H. Stiebig, C. Ulrichs, T. Kulessa, J. Folsch, F. Finger, H. Wagner, TRANSIENT PHOTOCURRENT RESPONSE OF A-SI:H BASED THREE COLOR NIPIN DETECTORS, in ICAS 16, Kobe, Japan, Sep. 4-8 1995). Here .tau. is the lifetime of the charge carrier generated by the instant light and .mu. is its mobility.
A disadvantage of the known components described is that only up to three linear independent structural sensitivity paths can be detected with this construction of the layer system. As a result a comparatively expensive superposition of these three independent signals is required for color image processing.